text: Thermal treatment of milk by indirect heating (e.g. pasteurization) to reduce microbial load and increase shelf life is generally performed by a plate heat exchanger.  Heat exchanger surfaces can become fouled by adsorbed milk protein deposits.  Fouling is initiated by formation of a protein monolayer at room temperature, followed by heat induced aggregation and deposition of whey protein and calcium phosphate deposits.  Adsorbed proteins decrease efficiency of heat transfer and potentially affect product quality by preventing adequate heating of milk.